What’s the scale factor ?

Explanation:

The vertical side of the blue triangle is PR = 2

The corresponding vertical side of the green triangle is P'R' = 4

The scale factor is the ratio of those two corresponding sides. So we divide the two side lengths.

scale factor = (P'R')/(PR) = (4)/(2) = 2

We could also say:

scale factor = (R'Q')/(RQ) = (6)/(3) = 2

Or you could find the lengths of PQ and P'Q' through the distance formula, or Pythagorean theorem, and apply the same idea as shown above.

first one because it can't have a fraction in it

step-by-step explanation:

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